Scattering of pump electromagnetic wave in Thermal Cluster Plasma

Abstract

Abstract The existence of sub-micron sized clusters in a gas jet plasma dramatically alters the dispersion equations for electromagnetic and Langmuir waves. When a strong laser travels through such a plasma, stimulated Raman scattering, or SRS, takes place. The electromagnetic pump in SRS excites a side band wave and a Langmuir wave. The pump's oscillatory velocity mixes with the density disturbance caused by the Langmuir wave to produce a non-linear current density that drives the side band. The pump and side band wave exert a ponderomotive force on the electrons generating the Langmuir wave. The Langmuir wave is influenced by the plasma frequency and the thermal velocity of the plasma electrons.The impact of temperature on a short pulse laser stimulated Raman Scattering in a gas jet is examined embedded with atomic clusters.Due to a rise in the coupling constant, the growth rate of SRS increases as cluster density and electron thermal velocity increase., and frequency of the plasma wave,.Simulations have been carried out on Mathematica Version 8 to obtain the Normalized growth rate of stimulated Raman back-scattered wave with respect to normalized cluster density